Please note that when I say "key role," I really mean, "Oh wow, this is big. Like bigger than that weird Brody drug trip from a few weeks ago." So you can still turn back now if you want to remain unspoiled!
Clark has been cast in the very important role of Carrie's (Clarie Danes) mom! There are no details regarding the what, where, when, why or how of her appearance on the Showtime drama, which recently finished filming its fourth season. But suffice it to say, this is big news.
What do you think of Clark's casting?
(Full Disclosure: TVGuide.com is owned by CBS, Showtime's parent company.)
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